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磁场对种子性能具有一定的影响作用,部分种子经磁化改性后能够提高产量。设计一种磁场强度和磁化时间均可调节的永磁种子磁化机,阐述该机的整体结构与工作原理,详细说明各关键部件的设计方案。该机适合于对各类种子进行批量化磁化改性处理。 相似文献
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Interactions of three heavy metal ions, Cu2+, Cd2+, and Pb2+, and, for comparison, Na+ with electrodialytic clay fractions (less than 2 μm in diameter) of four paddy soils as well as a yellow-brown soil as a control soil were evaluated based on measurements of the Wien effect in dilute suspensions with a clay concentration of 10 g kg?1 in four nitrate solutions of 2 × 10?4/z mol L?1, where z is the cation valence, and a nitric acid solution of 3 × 10?5 mol L?1. Field strengths ranging from 15 to 230 kV cm?1 were applied for measuring the electrical conductivities (ECs) of the suspensions. The mean free binding energies between the various cations and all of the soils determined from exchange equilibrium increased in the order: Na+ < Cd2+ < Cu2+ < Pb2+. In general, the ECs of the suspensions in the sodium nitrate solution were smaller than those of the suspensions in the heavy metal solutions because of the lower electrophoretic mobility of sodium compared to the divalent cations. In terms of relative electrical conductivity-field strength relationships, relative electrical conductivity (REC) of suspensions containing various cations at field strengths larger than about 50 kV cm?1 were in the descending order: Na+ > Cu2+ > Cd2+ > Pb2+ for all tested soils. A characteristic parameter of the REC-field strength curves, ΔREC200, REC at a field strength of 200 kV cm?1 minus that at the local minimum of the concave segment of the REC-field strength curves, characterized the strength of adsorption of the cations stripped off by the applied strong electrical field, and for all soils the values of ΔREC200 were generally in the order: Na+ < Cu2+ ≤ Cd2+ ≤ Pb2+. 相似文献
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磁场预处理对花椰菜花药培养的影响 总被引:3,自引:0,他引:3
采用磁场强度300,500,700mT预处理大部分花粉发育处于单核中期和单核靠边期的花蕾,以提高花椰菜花药培养的愈伤组织诱导率和绿苗分化率,结果表明,磁场预处理可以明显提高愈伤组织诱导率,以均匀磁场预处理30min、磁场强度为300mT的效果较好,提高诱导率28.87%;经过磁场预处理,两种不同培养基的愈伤组织诱导率的差异比对照间差异明显缩小,即经磁场预处理的材料对培养基的选择性降低;在同一种诱导出的愈伤组织绿苗分化率的差异更明显,M2培养基上诱导出的愈伤组织绿苗分化率比M1培养基上的愈伤组织平均高13.2%-26.2%。 相似文献
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磁场预处理对花椰菜花药培养的影响 总被引:2,自引:0,他引:2
本试验采用磁场预处理提高花椰菜花药培养诱导率,结果表明,磁场预处理可以明显提高诱导率,在均匀磁场中预处理30min,磁场强度以300mT效果较好,提高诱导率27.33%,经过磁场预处理后两种不同培养基的愈伤组织诱导率的差异比未预处理的对照明显缩小,即经磁场预处理的材料对培养基的选择性降低。在同一种诱导培养基上,经磁场预处理后产生的愈伤组织绿苗分化率比对照高4.1%-13.2%,在两种不同培养基上诱导出的愈伤组织绿苗分化率的差异更明显,M2培养基上诱导出的愈伤组织绿苗分化率比M1培养基上的愈伤组织平均高13.4%-28.4%。 相似文献
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研究了不同强度的磁场处理对油菜种子发芽率、发芽势的影响。结果表明,磁场为0~795 mT处理油菜种子,将会增大种子的发芽势和发芽率;在620~795 mT对油菜种子的发芽势和发芽率有最佳的促进效果。当磁场强度超过795 mT时,会对种子的发芽势和发芽率产生抑制作用。 相似文献
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